A NUMERICAL INVESTIGATION INTO THE FLOW-FIELD AROUND A WORKER POSITIONED BY AN EXHAUST OPENING

A numerical investigation has been made into the flow behaviour near a worker in the vicinity of an exhaust opening. The flow field is that induced by the withdrawal of air through the exhaust opening and hence a wake forms between the worker and the opening. Both laminar and turbulent flow regimes are considered. The numerical technique adopted is the control volume, finite-difference method with the k-epsilon model used to model the turbulent flow. The problem has been considered in two dimensions in order to gain a greater understanding of the flow behaviour but the numerical method adopted could be extended to investigate three-dimensional effects. An investigation is made into the effects upon the flow of the distance of the worker from the exhaust opening for different operating conditions. The results show that if the worker is close to the exhaust opening then the how is steady and a small area of recirculating flow exists in the wake of the person. However, if the worker is situated some distance away from the opening then the flow field is unsteady with vortex shedding occurring in the persons wake.